Killzone + motorstorm
I've seen these over and over, and also on TV recently (Motors TV had some good footage). Looking at them closely, I think you could get that kind of quality next gen - at least I'd hope so.
In some ways Killzone isn't *that* graphically impressive. Good draw distance, some OK character models (but not the best I've seen from even this gen) and lots of people on screen at once. Oh, and I agree about the smoke/bombs stuff - v.nice.
And motorstorm had a brief 3rd person cam view that looked like a souped up ATV offroad. So most of that can be done (AA and motion blur maybe less so)